docs: def to_json(self):
          """
          Represented as a list of edges:
              dependent: index of child
              dep: dependency label
              governer: index of parent
              dependentgloss: gloss of parent
              governergloss: gloss of parent
          """
          edges = []
          for root in self.roots:
              edges.append({
                  'governer': 0,
                  'dep': "root",
                  'dependent': root+1,
                  'governergloss': "root",
                  'dependentgloss': self.sentence[root].word,
                  })
  
          for gov, dependents in self.graph.items():
              for dependent, dep in dependents:
                  edges.append({
                      'governer': gov+1,
                      'dep': dep,
                      'dependent': dependent+1,
                      'governergloss': self.sentence[gov].word,
                      'dependentgloss': self.sentence[dependent].word,
                      })
          return edges